As a method of inputting or selecting a character by a manipulation of pressing a key such as a character key and a numeric key with a remote controller of audio-visual equipment such as a television set or with a mobile phone, the following techniques are known.
What is widely known is a method in which a plurality of characters is assigned to each numeric key, and the character to be the input candidate is changed in accordance with the number of times that the key is pressed. In this method, 50 syllabary kana or katakana characters, 26 alphabetical characters and the like can be input with small number of keys. According to such a method of inputting many characters with small number of keys, what is generally employed is a manipulation method in which a precedently input character is confirmed based on a key manipulation of inputting the next different character, or a manipulation of shifting the cursor using a four-way key. What is meant by confirming an input character is to determine to use a character candidate having been input for a character string such as text being prepared, and to prepare for an input work of the next character.
Another known input character confirming method is an input character confirming method that has a function of automatically confirming a character being input via a numeric key after a lapse of a predetermined waiting time. When the character is confirmed, such a confirmation is announced by a beeper or the like, and then the next character input is accepted. According to this method, key manipulation for a confirmation is unnecessary (e.g., see Patent Document 1).
There is also known a method in which, when one of the numeric keys is manipulated, a plurality of kana characters or a plurality of alphabetical characters previously assigned to the numeric key is successively displayed on a display unit as time passes and when any numeric key or a key for a confirmation is manipulated, the character being displayed on the display unit is confirmed as the input character. What is required is just to wait appearance of the desired character, and to manipulate the key for a confirmation. Therefore, it becomes possible to reduce the number of times of manipulating the key for searching for the assigned one of the characters (e.g., see Patent Document 2).
Further, there is a method in which, in a case where a plurality of characters is assigned to each numeric key, the displaying color of the numeric key is successively varied at predetermined timing, and the character is selected based on a manipulation timing of the numeric key (e.g., see Patent Document 3).
However, each method described in Patent Documents 1, 2, and 3 is unclear as to the timing at which the character is confirmed, and may invite an unintended selection. That is, user unaccustomed to the automatic confirmation cannot predict how long it takes before a confirmation is made, and may select wrong one, e.g., the user may press the key immediately after an automatic confirmation. For example, in a case where “a”, “i” and “u” are assigned to an identical key and in a state where “i” is being displayed, when the user, who is not aware of “i” having already been automatically confirmed, further presses the key for changing “i” to “u”, what is entered is “a” because “i” has already been confirmed. This makes the user confused.